Tailstock



W. F. GROENE.

I TAILSTOCK. I APPLICATION FILED SEPT. 22, 1919. 1,361 ,792. Patented Dec. 7, 1920;

2 SHEETS-SHEET 1- l l l I I I a InvenL or:

W. F. GROENE.

TAILSTOCK.

APPLICATION FILED SEPT. 22, 1919.

Patented Dec. 7, 1920.

2 SHEETS-SHEET 2.

. nvenl or:

UNlTED STATES wrnmamne'norinn; or cincmn'ari, omdnssrenon TO THE R. 1:. LE 3m macmnr. roo'L. country, or cmcmna'rronm a' conronnrron or omo.

' f 'rains'rocxf To all whom/it may comm.-

Be it known that I, WILLIAM F. GnonNn,

- a citizen of the United States, residing at Cincinnati, in the county of Ha 'ltonand State of Ohio,have invented an mprove- 'ment in "Tail'stocks,ofwhich the following description, in connection with the accompanying drawings, is; a specification, like characters on the drawings representing like parts. j

.The invention. to be hereinafter described relates to tail stocks for lathes and other machine tools, and moreparticularly to improved means for adjusting andsecuring the dead'spindle of the. tail stock.

In the use of tailstocks as heretofore constructed,. considerable care must be exercised in adjusting the dead center into engagement with the work with the correct amount of pressure. If the center forced in too tightly, rotation of the work with respect to the tail stock is liable to develop heat suflicien't to burn and injure the center. On the other hand, if the center is adjusted into too loose engagement with the work,

the operations on the latter will not be accurately' performed. Therefore, considerable judgment has been necessary in adjusting the center with the proper pressure against the Work, and there is always a chance that the correct adjustment will not be obtained.

One of the purposes of the present invention, therefore, is to provide means for adjusting the center into engagement with the work with provision for automatically obtaining the proper pressure Without reguiring attention on the part of the operator.

s a consequence, the center may be quickl adjusted into engagement with the wor without danger of burning the center or permitting lost motion'between the center and the work which would prevent accurate operations-on the work. 1

- Another purpose of the invention is to provide means for automatically clamping or securing the dead center spindle afterv it has been given the proper axial adjustment. Another purpose of the invention is to provide means for imparting the proper axial adjustment to the dead center spindle, and to secure the spindle in difi'erent positions of adjustment, all under the control of a single operating handle. the construc- 'tion being such that the adjustment and wherein I Specification of Letters Patent. P t t 1920 Application med September 22,;1919JSe r1alNo. 325,297..

' securing operations are progressively-perview, the character of the invention will be best understood by reference to the following description of one good form thereof shown 1n the accompanying "drawings,

- Figure 1 is a view partly in elevation PATEN'r-OFFICE.

and artly in section of a tail stock embodyin t einvention; and

1 2 1s a plan of the tail stock shown in Fig. 1 ,-certa1n parts thereof being'shown 1n section. Y i

Referring to the drawings, 1 designates a support which may be the bed of a lathe or other machine tool, and 2 designates the body of the tail stock provided with a doveta1 l base 3 adapted to slide in either of a air of dove-tall grooves 5 on said support.

he dove-tall 3- may be provided with a ib 7 connected to screws 9 and 11 projecti ng through bores in the body 2, said screws be- 1ng provided With adjusting nuts 13 and 15.

' The construction is such that the nuts may A center 21 has a tapered head 23 for engagement with the Work, and a tapered shank 25 adapted to be set with a'tiglit friction fit in the sleeve spindle 19. A-draw bolt 27 is mounted in a counterbore in the spindle sleeve, and is confined against axial' movement with respect to the boss 17 by a cap 29 having a collar 31 threaded to said boss. The inner end of the draw bolt has a head 33 adapted to engage the inner end of the center and release the same from the spindle on adjustment of the latter a sufficient distance toward the right of Fig. 2.-

Suitable means may be provided for imparting the axial movement to the spindle. To accomplish this, in the present instance, the spindle is provided with a rack 35 meshing with a gear 37 mounted in a bore in the head extending transversely to the spindle receiving bore referred to. The gear and a screw plu 37 is formed or secured on a sleeve shaft 39 projecting upwardly therefrom and beyond t e upper end of the head, where it is provided with a collar 41 for engagement with the up 'er' end" of the head to confine An operatin member or handle 51 is provided with a ub 53 threaded to a screw portion 55 of a stud shaft 57 projectin downward through the sleeve shaft 39 an beyond theear 37. A toe or lug 59 (Fig. 2) projects mm the handle hub 53 and 1s adapted to engage the spring-pressed plunger 45.

The construction. is such that when the handle 51 is rotated in a clockwise direction (Fig-2), the toe 59 will: press against the plunger 45 and through the coil spring 47, and the socket 43 will yieldingly impart rotative motion to the sleeve shaft 39 and the gear 37. Since the latter meshes with the rack 35, it will serve to adjust the dead spindle axially. The spindle will be moved until its center comes into on gement with and is arrested by the work. hereupon, any further movement of the, handle will merely vcompress the coil spring without transmit ting further movement to the spindle. The arrest of the spindle by enga ement with the work may be readily sense by the operator from the somewhat increased're'sist ance to the movement of the handle caused by the compression of the spring.

It is desirable to provide means for lockin the gear 37 a ainst rotation after the spindle center had een adjusted into proper engagement with the work as described, and be ore the spindle is secured in its position of adjustment. To accomplish this, in the present instance of the invention, the stud shaft 57 is connected to the sleeve shaft 39 by a spline 61, so that the two shafts will rotate to ether, but the stud shaft may move axially with respect to the sleeve shaft. Splined to the lower end of the stud shaft is a tapered ring 63 adapted to fit into the tapered bore of a bushing 65. secured in the bore or hearing receiving the gear 37 and at a point directly beneath the latter. The tapered ring 63 may be' secured to the stud shaft 57 by a nut 67 threaded on a reduced end of said shaft and bearing against the lower end of the ring. 4

The construction is such that after the spindle has been adjusted and arrested by engfigement of the center with the work, the ban e may turn somewhat further owing to adjusting gear against rotation, and third,

's indle in its position of a 'dle will automatically take effect after the the yield of the coil spring, thereby causing the threaded handlehub to act on the screw ortio'n 55 of the stud shaft and draw the atter upward axially. This will 'jam the tapered rin 63 into tight engagement .with the tape bore of t e bushing- 65,. and thereby prevent rotation of the' ear 37.

After the'gear has been locke against rotation as described, it is desirable to clamp or secure thespindle in its bearinga To ac.- complish this, in the present instarice, the upper endportion of the head 2 may be split by a kerf 69 extendin horizontally inward to the bearing ona ane transverse to the axis of the stud sha t 57. The construction is such that the handle may be turned some what after-securin the gear against rota-' tion, thereby screwing the handle hub farther down on the screw. portion 55 of the stud shaft, and since said hub engages'the flan e of the sleeve shaft resting on one end of t e bearing for the sleeve shaft and the tapered ring presses against the bushin which en ages the opposite end of sai bearin t is further movement of the handle wil serve to ress the portions. of he. head adjacent the kerf 69 toward each other and thereby contract the spindle bearing ti htl to secure the-spindle in its position o ad ustment. 7 Thus, it will be seen that the same handle may serve first, to adjust the spindle to bring its center into proper engagement with the work, second, to lock the spindle to contract the, spindle bearin to secure'the 'ustment, and t ese results are accomplished,in the present instance, by progressive moyements of the handle in the same direction of rotation. The gear locking device will automatically take effect when the spindle center has been arrested by proper engagement with the work, and the securing means for the spingear has been locked against rotation, all

without requiring attention on the part of the operator.

When it is desired to retract the spindle center from the work, the handle is turned somewhat in a contra-clockwise direction fgig. 2). This will allow the bearing for t e spindle to expalhd somewhat sufficientlyto release the spin le owing to the inherent resilience of the metal forming the bearing. This movement of the'handle will cause the handle hub to unscrew somewhat from the screw portion55 of the stud shaft, but the pitch of the ring 63 and bore. of the bushmg 65 is such that this movement of the handle will not release the ring from the bushing, and therefore, will not permit rotationof the gear until after the spindle has been released. Further movement of the socket 43 and through the latter the sleeve shaft will be positively turned somewhat, and since the stud shaft is splined to the sleeve shaft and the ring is splined tothe stud shaft, the ring will be turned relatively to the bushin sufficiently to release the ring therefrom. henfurther rotation of the handle will rotate the gear, and the latter meshing with the rack will serve to retract the spindle the distance desired' Thus, the handle when turned'in a contra-clockwise direction will serve first, to unclamp the spindle, second, to release the gear locking device, and third, to rotate the gear to adjust the spindle, and, the change from one operation to another will be automatically made without requiring attention on "the part of the operator.

It may be'desirable to vary the ressure of the spindle center against the wor This may readily be accomplished by adjustment of the screw plug 49 to vary t e tension of the coil spring 47.

By my invention, a simple and efiicient device is provided whereby the spindle center may be quickly and readily adjusted into proper engagement with the work so as to prevent any possibility of burning of the center or too loose engagement of the center with the work so as to result in imperfect work, and the center may be quickly and readily retracted from the work as desired.

It will be understood that the invention is not limited to the specific embodiment shown, and that various deviations maybe made therefrom without departing from the spirit and scope of the appended claims.

What is claimed is 1. A tail stock comprising ahead having a bore therein, a dead spindle movable axially in said bore, a rack on said spindle, a sleeve shaft rotatably mounted in said head, a gear fixed on said sleeve shaft meshing with said rack, an inner stud shaft within the sleeve shaft and non-rotatably secured thereto, an operatingme'mber rotatable independently of the sleeve shaft, and means including a spring between the operating member and sleeve shaft yieldingly to transmit movement from said operating member to said sleeve shaft.

2. .A tail stock comprising a head having a bore therein, a. dead spindle movable axially in said bore, a sleeve shaft mounted in said head, an inner stud shaft mounted in said sleeve shaft and movable axially of the sleeve shaft, an operating member rotatably mounted on said inner shaft, a spring to transmit rotary movement from said operating member to said sleeve shaft, and operating connections between the sleeve shaft and s indle.

3. tail stock comprising a head having a bearing, a dead spindle mounted for longitudinal movement in the bearing and having a rack, a sleeve shaft, a gear secured to the sleeve shaft and engagin the rack, a stud shaft extending through t e sleeve shaft and movable axially relative thereto,- a handle mounted forv rotative movement on the stud shaft, a spring for transmitting rotary movement of the handle to the sleeve shaft and connections between the stud shaft and handle for locking the sleeve shaft.

4. tail stock comprising a head having a bearing, a spindle mounted for longitudinal movement in the bearing, a rack and p1n1on for moving the spindle longitudinally, a locking device for locking the pinion, asecurmg device for securing the spindle in dlfferent positions of adjustment, a handle, and connections between the handle, the p1n1on, and securing devices for progressively' operating the pinion, locking the pinion, and securing the spindle.

5. In a device of the class described, the combination of a spindle having a rack, a

. pinion for advancing and retracting the spindle, a sleeve shaft to which the pinion is secured, a handle having a pro ection adapted to engage a part carried b the sleeve shaft for rotating the sleeve shaft and pinion, and yielding devices between the projection on the handle and part on the sleeve shaft for yieldingly advancing the spindle. I

6. In a tail stock, the combination of a spindle having rack teeth, a sleeve shaftcarrying a pinion meshing with the rack teeth, a stud shaft, a. handle rotatably mounted on the stud shaft and havin a projection, a spring between the projection and sleeve shaft for yieldingly rotating thelatter from the handle, and a threaded connection between the handle and stud shaft for locking the sleeve shaft and pinion. v

7. A tail stockcomprising a head having a bore therein, a dead spindle mounted in said bore, a pair of shafts one within the other and mounted for inde movements, a gear on one 0 said shafts, a rack on said spindle meshing with said gear, a handle mounted on the other of said shafts, means to transmit rotar motion from the handle to the shaft carrying the gear axially to slide said spindle, securing means for said spindle, and means to transmit axial movement from thehandle to its shaft to render the securing means effective.

8. A tail stock comprising a head having a bore therein, a dead spindle mounted in said bore, a rack for said spindle, a. sleeve shaft having a gear thereon meshing with said rack, a shaft rotative with but movable axially in said sleeve shaft, a handle on said 12 axially movable shaft, a conical seat in said head, a conical member on the axially movable shaft for engagement with said seat, and spring means yieldingly to impart rotary movement from said handle to said ndent rotary 110 sleeve shaft axially to move said spindle said handle having a hub threaded on sai axially movable shaft for adjusting the latter to tighten the conical member into the conical seat, to prevent rotation of said shafts and to draw portions of said head into clamping relation with said spindle.

9. A tail stock comprising a head havin a split bearing, a spindle mounted in sai bearing, and means including a handle for shifting said spindle axially in said bearing until limited by engagement with a piece of work and then automaticall acting by further' movement of the hand es for contracting said 5 lit bearing into secure gripping relation with said spindle.

10. A tail stock comprising a head having a split bearing, a spindle mounted in said bearing, a sleeve shaft, means to transmit motion from said sleeve shaft to said spindle to slide thelatter axially in said bearing,

13. A tail stock comprising a head havin a split bearing, a spindle mounted in sai bearing, a devlce for adjusting said spindle axially in said bearing, a locking device for said adjusting device, a securing device for contractin said bearing to secure the spindle in di erent positions of adjustment, a

- handle, and connections between said hana clamp shaft projecting through said sleeve transversely to said bearing, and "a handle and yielding connections for rotating said sleeve shaft to slide said spindle and for axially adjusting said clamp shaft to contract said split bearing into secure gripping relation with said spindle.

11. A tail stock comprising a head having a split bearing, a spindle mounted in said bearing, a sleeve shaft, a clamp shaft mounted in said sleeve shaft, devices on said sleeve shaft and clamp shaft for contracting said bearing tightly to said spindle on relative axial adjustment of: said, shafts, means for transmitting movement from said sleeve shaft to said spindle axially to adjust the latter, a handle, means to impart rotary movement from said handle to said sleeve shaft, and means actuated by said handle to produce the relative axial adjustment of said shafts for clamping the bearing to thespindle.

12. A tail stock comprising a head having a split bearing, a spindle mounted in said bearing, a device for adjusting said spindle axially in said bearing, a securing devlce for contracting said bearing to secure the spindle in different positions of adjustment, an operating handle and connections between said handle and said adjusting and securing devices for progressively rendering the same effective in the order named on movement of said handle.

dle and devices for progressively rendering the same effective in the order named;

' 14. A tail stock comprising a head havin a split bearing, a spindle mounted in sai bear1ng, a device for adjusting said spindle axially in said bearing, a locking device for said adjusting device, a securing device for -moving said spindle axially into engagement with a piece of work, and means for varying the compressing tension of. said spring for adjustably determining the pressure of the spindle against the work.

16. A tail stock comprising a head having a spllt portion with a bore therein, a dead spindle mounted in said bore and having a rack, agear meshing with said rack, a sleeve proecting from said gear and having a socket therein, a spring-pressed plunger mounted in said socket, a stud in said sleeve having a tapered element at one end thereof, a handle having a hub threaded on said stud and a member projecting from said hub to engage said spring-pressed plunger and turn said gear to advance said rack and s indle on a preliminary movement of said handle and to screw said hub down on said stud and press the split portion of the head tightly to said spindle on further movement of sa d handle.

In testimony whereof,- I have signed my name to this specification.

WILLIAM F. GROENE. 

